Two hundred Romans, and no one’s got a pen? Never mind!" He slung his M16 onto his back and pulled out a hand grenade. There were many screaming Romans. Then the hand grenade morphed into a ballpoint pen, and Mars began to write. Frank looked at Percy with wide eyes. He mouthed: Can your sword do grenade form?Percy mouthed back, No. Shut up.

- Rick Riordan